Alert archive / Pennsylvania / Flash Flood Warnings in 2025
Flash Flood Warning 39, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this flash flood warning at Jul 8, 2025, 4:39 PM EDT for Chester County, Pennsylvania. It was in force for 4 hr. 3 reports came from inside the area while it was in force.
The area
The outline as issued, with what was reported inside it.
The facts
- Issued
- Jul 8, 2025, 4:39 PM EDT (20:39 UTC)
- Expired
- Jul 8, 2025, 8:45 PM EDT
- In force
- 4 hr
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
- Flood severity
- None
County Chester County, PA
The radar
The Dover AFB radar (KDOX), 125 km from the middle of the area, began a volume at 20:42 UTC, the scan nearest the moment this went out.
Open the radar archive at this moment
The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| Jul 8, 5:28 PM EDT | FLASH FLOOD | Coatesville, PA | Water rescue on Merchant St. |
| Jul 8, 5:30 PM EDT | RAIN 1.56 | Atglen, PA | 1.56 inches per hour from DEOS. |
| Jul 8, 6:00 PM EDT | FLASH FLOOD | 1 Wnw Oxford, PA | Oxford Exit on Route 1 flooded out. Time given in report. |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
The nearest sounding before it
Washington/Dulle, VA (KIAD), launched 12:00Z, 8.7 hours before the alert went out and 163 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.
- Mixed-layer CAPE
- 695 J/kg
- Mixed-layer CIN
- -87 J/kg
- Mixed-layer LCL
- 1207 m above ground
- 0-6 km bulk shear
- 29 kt
- 0-1 km storm-relative helicity
- 7 m²/s²
- 0-3 km storm-relative helicity
- 55 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.1
The text
As transmitted.
148
WGUS51 KPHI 082039
FFWPHI
PAC029-090045-
/O.NEW.KPHI.FF.W.0039.250708T2039Z-250709T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
439 PM EDT Tue Jul 8 2025
The National Weather Service in Mount Holly has issued a
* Flash Flood Warning for...
Southwestern Chester County in southeastern Pennsylvania...
* Until 845 PM EDT.
* At 439 PM EDT, Doppler radar indicated thunderstorms producing
heavy rain across the warned area. Between 0.5 and 1 inch of rain
has fallen. The expected rainfall rate is 2.5 to 3.5 inches in 1
hour. Additional rainfall amounts of 1.5 to 2.5 inches are
possible in the warned area. Flash flooding is ongoing or expected
to begin shortly.
HAZARD...Flash flooding caused by thunderstorms.
SOURCE...Radar.
IMPACT...Flooding of small creeks and streams, urban areas,
highways, streets, and underpasses as well as other
drainage and low lying areas.
* Some locations that may experience flash flooding include...
Coatesville, Oxford, Parkesburg, Cochranville, Homeville, Mount
Vernon, Atglen, South Coatesville and Modena.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around...don't drown when encountering flooded roads. Most
flood deaths occur in vehicles.
Move to higher ground now. Act quickly to protect your life.
&&
LAT...LON 3997 7571 3994 7573 3992 7572 3988 7576
3980 7592 3978 7598 3977 7606 3980 7604
3980 7605 3981 7603 3983 7604 3983 7602
3985 7602 3987 7599 3991 7600 3993 7600
3993 7598 3995 7599 3997 7599 4000 7582
FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL RATE...2.5-3.5 INCHES IN 1 HOUR
$$
Hoeflich3 follow-up statements
319
WGUS71 KPHI 082134
FFSPHI
Flash Flood Statement
National Weather Service Mount Holly NJ
534 PM EDT Tue Jul 8 2025
PAC029-090045-
/O.CON.KPHI.FF.W.0039.000000T0000Z-250709T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Chester PA-
534 PM EDT Tue Jul 8 2025
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 845 PM EDT THIS
EVENING FOR SOUTHWESTERN CHESTER COUNTY...
At 534 PM EDT, local law enforcement reported thunderstorms
producing heavy rain with water rescues reported in Coatesville.
Between 1.5 and 2.5 inches of rain have fallen. The expected
rainfall rate is 2.5 to 3.5 inches in 1 hour. Additional rainfall
amounts of 0.5 to 1.5 inches are possible in the warned area. Flash
flooding is already occurring.
HAZARD...Flash flooding caused by thunderstorms.
SOURCE...Law enforcement reported.
IMPACT...Flooding of small creeks and streams, urban areas,
highways, streets, and underpasses as well as other
drainage and low lying areas.
Some locations that may experience flash flooding include...
Coatesville, Oxford, Parkesburg, Cochranville, Homeville, Mount
Vernon, Atglen, South Coatesville and Modena.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around...don't drown when encountering flooded roads. Most
flood deaths occur in vehicles.
Move to higher ground now. Act quickly to protect your life.
&&
LAT...LON 3997 7571 3994 7573 3992 7572 3988 7576
3980 7592 3978 7598 3977 7606 3980 7604
3980 7605 3981 7603 3983 7604 3983 7602
3985 7602 3987 7599 3991 7600 3993 7600
3993 7598 3995 7599 3997 7599 4000 7582
FLASH FLOOD...OBSERVED
EXPECTED RAINFALL RATE...2.5-3.5 INCHES IN 1 HOUR
$$
Hoeflich570
WGUS71 KPHI 082318
FFSPHI
Flash Flood Statement
National Weather Service Mount Holly NJ
718 PM EDT Tue Jul 8 2025
PAC029-090045-
/O.CON.KPHI.FF.W.0039.000000T0000Z-250709T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Chester PA-
718 PM EDT Tue Jul 8 2025
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 845 PM EDT THIS
EVENING FOR SOUTHWESTERN CHESTER COUNTY...
At 718 PM EDT, local law enforcement reported thunderstorms
producing heavy rain in Coatesville with water rescues reported.
Between 2 and 3 inches of rain have fallen. Flooding impacts will
continue, but no additional rainfall is expected. Flash flooding is
already occurring.
HAZARD...Flash flooding caused by thunderstorms.
SOURCE...Law enforcement reported.
IMPACT...Flooding of small creeks and streams, urban areas,
highways, streets, and underpasses as well as other
drainage and low lying areas.
Some locations that may experience flash flooding include...
Coatesville, Oxford, Parkesburg, Cochranville, Homeville, Mount
Vernon, Atglen, South Coatesville and Modena.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around...don't drown when encountering flooded roads. Most
flood deaths occur in vehicles.
&&
LAT...LON 3997 7571 3994 7573 3992 7572 3988 7576
3980 7592 3978 7598 3977 7606 3980 7604
3980 7605 3981 7603 3983 7604 3983 7602
3985 7602 3987 7599 3991 7600 3993 7600
3993 7598 3995 7599 3997 7599 4000 7582
FLASH FLOOD...OBSERVED
$$
Hoeflich021
WGUS71 KPHI 090035
FFSPHI
Flash Flood Statement
National Weather Service Mount Holly NJ
835 PM EDT Tue Jul 8 2025
PAC029-090045-
/O.EXP.KPHI.FF.W.0039.000000T0000Z-250709T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Chester PA-
835 PM EDT Tue Jul 8 2025
...FLASH FLOOD WARNING WILL EXPIRE AT 845 PM EDT THIS EVENING FOR
SOUTHWESTERN CHESTER COUNTY...
Flood waters have receded. The heavy rain has ended. Flooding is no
longer expected to pose a threat. Please continue to heed remaining
road closures.
&&
LAT...LON 3997 7571 3994 7573 3992 7572 3988 7576
3980 7592 3978 7598 3977 7606 3980 7604
3980 7605 3981 7603 3983 7604 3983 7602
3985 7602 3987 7599 3991 7600 3993 7600
3993 7598 3995 7599 3997 7599 4000 7582
$$
HoeflichThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 7, 10:59 PM EDT | Flood Watch | PHI | Berks, Bucks, Chester, Delaware, Lehigh, Montgomery and 2 more | 23 hr |
| Jul 8, 3:04 PM EDT | Severe Thunderstorm Warning | PHI | Berks | 41 min |
| Jul 8, 3:44 PM EDT | Severe Thunderstorm Warning | PHI | Berks | 46 min |
| Jul 8, 4:05 PM EDT | Flash Flood Warning | PHI | Berks | 4 hr |
| Jul 8, 4:20 PM EDT | Severe Thunderstorm Warning | PHI | Chester | 40 min |
| Jul 8, 4:25 PM EDT | Severe Thunderstorm Warning | PHI | Berks | 35 min |
| Jul 8, 4:33 PM EDT | Severe Thunderstorm Warning | PHI | Berks, Chester, Montgomery | 42 min |
| Jul 8, 4:54 PM EDT | Severe Thunderstorm Warning | PHI | Berks, Chester, Montgomery | 51 min |
| Jul 8, 4:56 PM EDT | Severe Thunderstorm Warning | PHI | Chester | 19 min |
| Jul 8, 5:02 PM EDT | Flash Flood Warning | PHI | Chester | 4 hr |
| Jul 8, 5:16 PM EDT | Severe Thunderstorm Warning | PHI | Bucks, Chester, Delaware, Montgomery, Philadelphia | 29 min |
| Jul 8, 5:19 PM EDT | Tornado Warning | PHI | Bucks, Montgomery | 26 min |
| Jul 8, 5:20 PM EDT | Tornado Warning | PHI | Chester, Delaware, Montgomery, Philadelphia | 25 min |
| Jul 8, 5:31 PM EDT | Flash Flood Warning | PHI | Chester, Delaware | 4 hr |
| Jul 8, 5:34 PM EDT | Severe Thunderstorm Warning | PHI | Bucks, Delaware, Montgomery, Philadelphia | 41 min |
| Jul 8, 5:45 PM EDT | Flash Flood Warning | PHI | Chester, Delaware, Montgomery, Philadelphia | 4 hr |
| Jul 8, 5:46 PM EDT | Severe Thunderstorm Warning | PHI | Delaware, Philadelphia | 44 min |
| Jul 8, 5:52 PM EDT | Tornado Warning | PHI | Bucks, Montgomery, Philadelphia | 13 min |
| Jul 8, 5:53 PM EDT | Flash Flood Warning | PHI | Bucks, Montgomery, Philadelphia | 4 hr |
| Jul 8, 5:56 PM EDT | Severe Thunderstorm Warning | PHI | Bucks, Philadelphia | 49 min |
| Jul 8, 6:08 PM EDT | Severe Thunderstorm Warning | PHI | Bucks | 34 min |
Nearby
Flash Flood Warnings in Pennsylvania, 2025Every flash flood warning in 2025
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.